Patent GB-899824-A (GB)
Title: Surface-active acetals and formals
Filed: 1958-09-23
Abstract: Hydrocarbon oils may be emulsified with water using 0,1 to 1% of an acid sensitive non-ionic surface-active acetal or formal of the general formula <FORM:0899824/III/1> to give emulsions which can be broken by treatment with a dilute acid at elevated temperature.  In the above formula, R is a hydrogen atom or an alkyl group, R1 is an alkyl group, there being a total of 8-24 carbon atoms in each pair of R and R1 taken together, R2 is a hydrogen atom or a methyl group, A is an oxygen or sulphur atom and n is an integer from 6 to about 50, or a mixture of such compounds containing different numbers of ethenoxy groups, the average value of n being from 6 to about 50.ALSO:The invention comprises compounds of the general formula <FORM:0899824/IV (a)/1> where R is a hydrogen atom or alkyl group, R1 is an alkyl group, there being a total of from 8 to 24 carbon atoms in R and R1 taken together, R2 is a hydrogen atom or a methyl group, A is oxygen or sulphur and n is an integer from 6 to about 50 and mixture of such compounds containing different numbers of ethenoxy groups, the average value of n being from 6 to 50.  The compounds may be prepared by reacting two mols. of a compound of the formula <FORM:0899824/IV (a)/2> where X is chlorine or bromine with a glycol of the formula HO(CH2CH2O)nH in the presence of a strongly basic inorganic neutralizing agent, for example potassium hydroxide, at about 50 DEG -70 DEG C.  Alternatively, when an acetal is desired, i.e. R2 is a methyl group, 2 mols. of a vinyl ether of the formula <FORM:0899824/IV (a)/3> may be reacted with a glycol HO(CH2CH2O)nH in the presence of an acid such as hydrochloric or phosphoric acids, boron trifluoride or its co-ordination complexes.  Many reactants for both methods are listed and examples are given.  Oil-water emulsions containing the novel compounds as emulsifier may be broken on acidification of the emulsion.ALSO:The invention comprises compounds of the general formula <FORM:0899824/IV (b)/1> where R is a hydrogen atom or alkyl group, R1 is an alkyl group, there being a total of from 8 to 24 carbon atoms in each pair of R and R1 taken together, R2 is a hydrogen atom or a methyl group, A is oxygen or sulphur and n is an integer from 6 to about 50 and mixtures of such compounds containing different numbers of ethenoxy groups, the average value of n being from 6 to about 50.  The compounds may be prepared by reacting two mols of a compound of the formula <FORM:0899824/IV (b)/2> where X is chlorine or bromine with a glycol of the formula HO(CH2CH2O)nH in the presence of a strongly basic inorganic neutralising agent, for example potassium hydroxide, at about 50 DEG C.-70 DEG C.  Alternatively, when an acetal is desired, i.e. R2 is a methyl group, 2 mols of a vinyl ether of the formula <FORM:0899824/IV (b)/3> may be reacted with a glycol HO(CH2CH2O)2H in the presence of an acid such as hydrochloric or phosphoric acids, boron trifluoride or its coordination complexes.  Many reactants for both methods are listed and examples are given.  Oil-water emulsions containing the novel compounds as emulsifier may be broken on acidification of the emulsion.